Summary
In Arabidopsis thaliana, a family of four genes (HY1, HO2, HO3 and HO4) encode haem oxygenase (HO), and play a major role in phytochrome chromophore biosynthesis. To characterize the ...contribution of the various haem oxygenase isoforms involved in salt acclimation, the effects of NaCl on seed germination and primary root growth in Arabidopsis wild‐type and four HO mutants (hy1‐100, ho2, ho3 and ho4) were compared. Among the four HO mutants, hy1‐100 displayed maximal sensitivity to salinity and showed no acclimation response, whereas plants over‐expressing HY1 (35S:HY1) exhibited tolerance characteristics. Mild salt stress stimulated biphasic increases in RbohD transcripts and production of reactive oxygen species (ROS) (peaks I and II) in wild‐type. ROS peak I‐mediated HY1 induction and subsequent salt acclimation were observed, but only ROS peak I was seen in the hy1‐100 mutant. A subsequent test confirmed the causal relationship of salt acclimation with haemin‐induced HY1 expression and RbohD‐derived ROS peak II formation. In atrbohD mutants, haemin pre‐treatment resulted in induction of HY1 expression, but no similar response was seen in hy1‐100, and no ROS peak II or subsequent salt acclimatory responses were observed. Together, the above findings suggest that HY1 plays an important role in salt acclimation signalling, and requires participation of RbohD‐derived ROS peak II.
The inspiral of compact stellar objects into massive black holes are one of the main astrophysical sources for the Laser Interferometer Space Antenna (LISA) and Taiji. These extreme-mass-ratio ...inspirals (EMRIs) have great potential for cosmology and fundamental physics. A binary extreme-mass-ratio inspiral (b-EMRI) describes the case where binary black holes (BBHs) are captured by a supermassive black hole. The b-EMRIs serve as multi-band gravitational wave sources and provide insights into the dynamics of nuclei and tests of general relativity. However, if the b-EMRIs can be distinguished from the normal EMRIs or not is still not clear. In this work, with a few of assumptions, and using the Teukolsky equation, we calculate the approximate gravitational waves of b-EMRIs and assess their detectability by space-based detectors. We also decouple the secondary object information from the Teukolsky equation, enabling us to calculate the energy fluxes and generate the waveforms more conveniently. Variations in the quadrupole of the binary result in small but non-negligible changes in energy fluxes and waveforms, making it possible to distinguish b-EMRI signals with data analysis. This opens up the potential of using b-EMRIs to test gravity theories and for further astrophysical studies.
Yellow catfish (Pelteobagrus fulvidraco) has become a commercially important fish species in China and eastern Asia. High-density aquaculture has led to congestion and excessive stress and ...contributed to bacterial infection outbreaks that have caused high mortality. We investigated the effects of dietary supplementation with astaxanthin and emodin alone and in combination on the growth and stress resistance of yellow catfish. After 60 days of feeding, each group of fish (control, astaxanthin, emodin, and astaxanthin plus emodin (combination) groups) was exposed to acute crowding stress for 24 h, and a subsample of fish from the four groups was challenged with the bacterial septicemia pathogen Proteus mirabilis after the end of the crowding stress experiment. Compared with the control, the astaxanthin and emodin groups showed increases in serum total protein (TP), hepatic superoxide dismutase (SOD) activity and hepatic heat shock proteins 70 (HSP70) mRNA levels at 12 and 24 h after the initiation of crowding stress. The combination group exhibited increases in alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, serum TP, hepatic SOD activity and hepatic HSP70 mRNA levels within 24 h after the initiation of crowding stress. However, decreases relative to the control were observed in the serum cortisol and glucose contents in the three treatment groups at 12 and 24 h after the initiation of crowding stress, in ALT and AST activity in the astaxanthin and emodin group at 24 h after the initiation of crowding stress, and in the serum lysozyme activity, serum alkaline phosphatase (ALP) activity, and hepatic catalase (CAT) and malondialdehyde (MDA) activity in the combination group at 24 h after the initiation of crowding stress. Additionally, the cumulative mortality after P. mirabilis infection was lower in all three treatment groups (57.00%–70.33%) than in the control (77.67%). Dietary supplementation with astaxanthin and emodin decreased the specific growth rate (SGR) and weight gain (WG) of healthy yellow catfish, although significant differences in mortality were not observed. These results indicate that dietary supplementation with 80 mg/kg astaxanthin and 150 mg/kg emodin can improve the anti-oxidative capabilities, hepatic HSP70 levels, and resistance to acute crowding stress of yellow catfish. Finally, an appropriate strategy for enhance yellow catfish stress resistance and disease resistance is proposed.
•Astaxanthin and emodin increase the stress resistance and immunity of fish.•Astaxanthin and emodin can affect the expression of HSP70 in fish.•Astaxanthin and emodin synergistically enhance immunity in fish.
Agriculture is the foundation of social development. Under the pressure of population growth, natural disasters, environmental pollution, climate change, and food safety, the interdisciplinary “new ...agriculture” is becoming an important trend of modern agriculture. In fact, new agriculture is not only the foundation of great health and new energy sources, but is also the cornerstone of national food security, energy security, and biosafety. Hydrogen agronomy focuses mainly on the mechanism of hydrogen gas (H
2
) biology effects in agriculture, and provides a theoretical foundation for the practice of hydrogen agriculture, a component of the new agriculture. Previous research on the biological effects of H
2
focused chiefly on medicine. The mechanism of selective antioxidant is the main theoretical basis of hydrogen medicine. Subsequent experiments have demonstrated that H
2
can regulate the growth and development of plant crops, edible fungus, and livestock, and enhance the tolerance of these agriculturally important organisms against abiotic and biotic stresses. Even more importantly, H
2
can regulate the growth and development of crops by changing the soil microbial community composition and structure. Use of H
2
can also improve the nutritional value and postharvest quality of agricultural products. Researchers have also shown that the biological functions of molecular hydrogen are mediated by modulating reactive oxygen species (ROS), nitric oxide (NO), and carbon monoxide (CO) signaling cascades in plants and microbes. This review summarizes and clarifies the history of hydrogen agronomy and describes recent progress in the field. We also argue that emerging hydrogen agriculture will be an important direction in the new agriculture. Further, we discuss several scientific problems in hydrogen agronomy, and suggest that the future of hydrogen agronomy depends on contributions by multiple disciplines. Important future research directions of hydrogen agronomy include hydrogen agriculture in special environments, such as islands, reefs, aircraft, and outer space.
Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem with 90% of the ...total reported cases in the world. This study describes the spatiotemporal dynamics of HFRS cases in China and identifies the regions, time, and populations at highest risk, which could help the planning and implementation of key preventative measures.
Data on all reported HFRS cases at the county level from January 2005 to December 2012 were collected from Chinese Center for Disease Control and Prevention. Geographic Information System-based spatiotemporal analyses including Local Indicators of Spatial Association and Kulldorff's space-time scan statistic were performed to detect local high-risk space-time clusters of HFRS in China. In addition, cases from high-risk and low-risk counties were compared to identify significant demographic differences.
A total of 100,868 cases were reported during 2005-2012 in mainland China. There were significant variations in the spatiotemporal dynamics of HFRS. HFRS cases occurred most frequently in June, November, and December. There was a significant positive spatial autocorrelation of HFRS incidence during the study periods, with Moran's I values ranging from 0.46 to 0.56 (P<0.05). Several distinct HFRS cluster areas were identified, mainly concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties.
This study identified significant space-time clusters of HFRS in China during 2005-2012 indicating that preventative strategies for HFRS should be particularly focused on the northeastern, central, and eastern of China to achieve the most cost-effective outcomes.
Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the ...potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized.
This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease.
Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted.
During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation.
The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country.
Results from our previous study suggested that haem oxygenase-1/carbon monoxide (HO-1/CO) acts as a downstream signal system in the auxin-induced pathway leading to cucumber (Cucumis sativus) ...adventitious root formation. The objective of this study was to test whether HO-1 is also involved in hydrogen sulfide (H2S)-induced adventitious root formation. Cucumber explants were treated with HO-1 inducer haemin and H2S donor sodium hydrosulfide (NaHS) in combination with the specific inhibitor of HO-1 zinc protoporphyrin IX (ZnPPIX), and their effects on cucumber adventitious root development in IAA-depleted explants were compared. The results showed that similar to inducible responses of haemin, NaHS brought about the induction of cucumber HO-1 transcripts (CsHO-1) and its protein levels, and thereafter adventitious root formation. A further experiment verified that H2S or HS- rather than other sulfur-containing components derived from NaHS was ascribed to the stimulation response. The inducible effect is specific for CsHO-1 because ZnPPIX significantly suppressed the above responses, and the inhibitory effects were reversed partially when 30% CO-saturated aqueous solution was added. Molecular evidence further suggested that the NaHS-triggered upregulation of target genes responsible for HO-1/CO-induced adventitious root formation, including CsDNAJ-1 and CsCDPK1/5, was inhibited significantly by ZnPPIX. These decreases were reversed obviously by the addition of CO aqueous solution. However, hypotaurine (HT), the H2S scavenger, could not influence the haemin- and CO-induced adventitious rooting in IAA-depleted cucumber explants. Together, the above results suggested that HO-1 was involved in H2S-induced cucumber adventitious root formation.
Scrub typhus is a vector-borne disease carried by the chigger mite. The aetiological agent is the rickettsia Orientia tsutsugamushi, which is endemic to several countries in the Asia-Pacific region, ...including China 1. It is also a travel-associated disease 2 and of great importance among military personnel 3, 4. During the Second World War, scrub typhus was associated with a higher case fatality ratio than any other infectious disease in the China-Burma-India theatre of operations 1,3. Clinical presentation in patients varies from asymptomatic to life-threatening disease 5, including acute hearing loss and multiple organ failure 6, 7. To date, there is still no effective and reliable human vaccine against scrub typhus and no point-of-care diagnostics available 1.
Scrub typhus is a vector-borne disease, which has recently reemerged in China. In this study, we describe the distribution and incidence of scrub typhus cases in China from 2006 to 2014 and quantify ...differences in scrub typhus cases with respect to sex, age, and occupation. The results of our study indicate that the annual incidence of scrub typhus has increased during the study period. The number of cases peaked in 2014, which was 12.8 times greater than the number of cases reported in 2006. Most (77.97%) of the cases were reported in five provinces (Guangdong, Yunnan, Anhui, Fujian, and Shandong). Our study also demonstrates that the incidence rate of scrub typhus was significantly higher in females compared to males (P < 0.001) and was highest in the 60-69 year age group, and that farmers had a higher incidence rate than nonfarmers (P < 0.001). Different seasonal trends were identified in the number of reported cases between the northern and southern provinces of China. These findings not only demonstrate that China has experienced a large increase in scrub typhus incidence, but also document an expansion in the geographic distribution throughout the country.
Indole acetic acid (IAA) is an important regulator of adventitious rooting via the activation of complex signaling cascades. In animals, carbon monoxide (CO), mainly generated by heme oxygenases ...(HOs), is a significant modulator of inflammatory reactions, affecting cell proliferation and the production of growth factors. In this report, we show that treatment with the auxin transport inhibitor naphthylphthalamic acid prevented auxin-mediated induction of adventitious rooting and also decreased the activity of HO and its by-product CO content. The application of IAA, HO-1 activator/CO donor hematin, or CO aqueous solution was able to alleviate the IAA depletion-induced inhibition of adventitious root formation. Meanwhile, IAA or hematin treatment rapidly activated HO activity or HO-1 protein expression, and CO content was also enhanced. The application of the HO-1-specific inhibitor zinc protoporphyrin IX (ZnPPIX) could inhibit the above IAA and hematin responses. CO aqueous solution treatment was able to ameliorate the ZnPPIX-induced inhibition of adventitious rooting. Molecular evidence further showed that ZnPPIX mimicked the effects of naphthylphthalamic acid on the inhibition of adventitious rooting, the down-regulation of one DnaJ-like gene (CSDNAJ-1), and two calcium-dependent protein kinase genes (CSCDPK1 and CSCDPK5). Application of CO aqueous solution not only dose-dependently blocked IAA depletion-induced inhibition of adventitious rooting but also enhanced endogenous CO content and up-regulated CSDNAJ-1 and CSCDPK1/5 transcripts. Together, we provided pharmacological, physiological, and molecular evidence that auxin rapidly activates HO activity and that the product of HO action, CO, then triggers the signal transduction events that lead to the auxin responses of adventitious root formation in cucumber (Cucumis sativus).
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